It likely only seemed like the entire arena to the one making the video.
That said, Biden has cheesed off a very wide swath of people, and while he will still carry Seattle, I imagine that he will have a difficult time carrying Seattle Hockey fans, and even among the vaxxed hockey fans not all will necessarily be in favour.
Lots of people are vaxxed because of what they perceive as coercion. They may attend hockey games, but won’t like the coercion.
It's possible that the community is Kraken up.
Not to mention that the Kraken play in Climate Promise Arena or “Woke” Arena.